Telephone-exchange system



A. LUNDELL. TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED OCT. 8, |917.

Patented Jan. 17, 1922.

6 SHEETS-SVHEET-l.

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h. SQ www w Ven/0 4f/ en I ande/ IIE A. E. LUNDEILL. TELEPHONE EXCHANGE' SYSTEM. APPLICATION FILED OCT- 8| |91?. r 1,403,862, ,Patented Jan. 17,1922.

6 SHEETS-SHEET 2.

#Wen/0k.' Awe/7 i ande/A A. E. LUNDELL. TELEPHONE EXCHANGE SYSTEM.

-APPLICATION FILED OCT- 8. 19|?- -Patented Jan. 1-7, 1922.

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. l f n @No QI @A H h he?? 4me/7 0046// y /fff/ A.E.LUNDELL TELEPHONE EXCHANGE SYSTEM. APPLICATION FILED ocT. a. 1911.

Patented Jan. 17, 1922,

6 SHEETS-SHEET 4- A.E.YLUNDELL. TELEPHONE EXCHANGE SYSTEM. I

APPLICATION FILED OCT. 8. 1917.

Patented Jan. 17, 1922.

6 SHEETS-SHEET 5.

A. E. LUNDELL.

TELEPHONIE EXCHANGE SYSTEM. APPLICATION FILED ocT. 8. 19u.

1,403,862. Patented Jan. 17,1922.

s 'sains-SHEET 6.

vissued to F. N.

desired party-on a party lino is controlled FATENT tJlTiFICE.`

Amann LUNDELL, or New Youn,k n. Y., assieiioa To wnsfrnnn ELECTRIC con- PANY, NCORPORATED, F 'N W' YORK,

N. Y., .A CORPORATION 0F NEW YORK.

TELEPHGNEEXCHANGE SYSTEM.

Application ined october s, 1917. seiiai No.

citizen ot the TJnited States. residing at'New York7 in the county of Bronx and State of New York, have invented certain new and useful Improvements in'Telephone-EX change Systeinsyof which the following isla full, clear, concise7 and exact description.

p This invention relates to selective signaling7 and more particularly .to party line selectivo signaling employed 1n telephone systems.

l-leretotore, in certain telephone systenis employing machine switching, suclnitor instance, as that disclosed b Patent 1,218.8(ll eeves, h arch 18, lill?, the selection of ringing current for party line ringing has been determined'byV a special segment carried by one or" the switches.

It is the object ot this invention Yto 1inproyo on such a systein by eliniinatingr this special ringing segment and producing,` the saine result by a new organization ot circuits in a more elticient iiianner.

A feature oiPA this invention is the provision ot n cans whereby the selection of the proper source et ringing current for 'signaling the by the registering iiieo'hanisins which are selectively operated to control the operation et autoniatic switches in establishingl conne"- tion to the desired party line.

@ther 'features orn the invention ,not reterred 4to above will niore clearly appear troni the following' description and clainis.

rlie drawing' when arranged with Fig. 2 to the right ot Fig. l., 3 below l, i 4l below Fig. 3, Fig. l6 below Je and 5 to th right @t Fi et, diaorfonrfiatically represents portion ai se -niechanical 'telephone system employing tle present invention. nly so niuch oil thesyst is shown as is deen ed necessary tor a clear understandiet the inyention.

V Vtor and `coiiltindcr described in itt and J.

Specification of Letters Patent.

lines in F 3 niaw be ot the saine type as the sequence switches.

It will be obvious to those skilled in the rt that other types ot switches and controla ling apparatus ot a widely varying" characv er may be employed without departing' trom the spirit oi" theinvention. i i

It will be assumed that a calling` subscriber at an fr operators position ata distant exchange (not shown) wishes to communicate with a called substation whose line terminates at a B operators position-at the exchange shown. The A operator coniniuni- Cates through a well-known order wire (not shown) with the B operator and transmits to her the nuniber o't the desired line which,

in the present crisee will be assumed to l c.

l'o. 765%. lThe B operator instructs the A operator to extend the calling; line through her cord circuit to a certain idle trunk leadinf the B opcrators position. Y Assumingl tirait this idle trunk is the one shown in F net ot sequence switch 100,- upper contact ot sequence switch spring i, contact ot hey U53 to ground 'tor nioring` the sequence switch out of position l and-into iosition 2. ln position 2 of the sequence switch 100. a circuit is completed from grounded battery. winding` 'if relay 801, lower and upper letthand contacts oi sequence switch spring SO2. co ductor 3037 lower contacts ot sequence switch spring` 105, back contact and letthaiid armature o t relay 10G to'ground. Relayv 301 conipletes a circuit troni grounded battery. power magnet or sequence switch 3X), lower right-hand contact ot sequence switch spring st, front contact and righi4` hand ariiiature or relay 301 to ground for moving' this sequence switch out ot' position l and .into position Ags soon as the sequence switch 30G leaves position l5. the original energizing` circuit ot relay 301 is opened. but this relayv is maintained ener- Patented Jan. 17, 1922.

i, the fr operator inserts lier plug lOl into a` Yacl; 102 provided at her position ui which .i to start a cord finder operating toy lco gized over a circuit extending from grounded battery, winding of relay 301, lower letthand and upper right-hand contacts ofV sequence switch spring 302, back contact and left-hand armature or relay 305 to ground.

l In position 2 of sequence switch 300, a circuit is completed from grounded battery,

winding of up-drive magnet 306, contact ot' sequence switch spring 307, front contact and right-hand armature et relay 301 to ground. Under the control of this magnet the brush shaft 308 of the cord finder is moved in an upward direction. As soon as the test brush 309engages the terminal 310 individual to the trunk assigned to .the A operator, a circuit is completed from grounded battery,

winding of relay 305, upper right-hand contact of sequence switchspring 311, brush 309, terminal 310, conductor 312, contactot sequence'switch spring 107, back contact and right-hand armaturev of relay 108, Vupper l 109 to ground.

right-hand contact of sequence switch spring Relay 305 completes a locking circuit for itself from grounded battery, winding of relay 305, lower contact of sequence switch spring 311, front contact and righthand armature of relay 305, brush 375, terminal 316, conductor 317, lower righthand and upper lett-hand contacts et sequence switchV spring 110, winding of relay 106, contact ot sequence switch spring 111 to ground. Relay 305, by attracting its -letthand armature, opens the circuit otrelay 301, but this relay 301 is still maintained energized until the brushes ot the cord finder are accurately centered upon the terminals ingot relay 301, front contact and lett-handl l4o 'individualto the assigned trunk.

Vmutator brush 315, to ground.

rIlliis circult extends from grounded battery, windarmature of relay 301, conductor 313, conducting segment ot commutator 314, com- As soon as the brushes are accurately centered tie conimutator brushV 315`engages an insulating segment, thereby causing the deenergization of relay 301. he retraction ot the righthand armature of relay 301 opens the circuit y of the up-drive magnet 306 and closes a circonductor 502, upper left-hand contact ot sequence switch spring 318, conductor 319, upper lefty-hand contact of sequence switch spring 320, conductor 321, lower left-hand contact of the allotter sequence switch spring 401, winding of relay 402, lower lett-hand contactV of allotter sequence switch spring 403, conductor 404, upper righthand contact of sequence switchspring 327 to Vgrounded batteryllelays 501 and 402gbecome energized. The relay 402 completes a locking circuit 'for itself from grounded battery, armature and front contact ot Vrelay 402, upper'contact of allottersequence spring 403, the winding of relay 402 and thence over the circuit previously described, to ground. A circuit is also completed by the depression otY No. 7 thousands key from ground, lower Contact of No. 7 Y thousands key, conductor', 503, left-hand winding ot relay 504, lower righthand Vcontact of se quence switch. spring 318to grounded battery, over the lcircuit previously described. Relay 504 becomes energized.

In response to thedepression of the No. 6 hundreds key,a circuit is completedfrom ground, upper contact of this key,conduc tor 505, left-handwinding of relay506, con-V ductor 507, lower left-hand contacto'tA sequence switch spring 360 te grounded bat-V tery at armature and front contact of relay 402 over the Acircuit previously described. Relay 5,06 becomes energized. A circuit is also completed from'ground, lower contact of the`No. 6 hundreds key, conductor 547, i right-hand winding of relay 508, lower letthand contact ot sequence switch 318 te grounded battery over the circuit previously described. Relay 508 becomes energized and completes a circuit from grounded battery through its inner armature and front 5 tens key, a circuit is completed from y hand'winding of relay 510, upper lett-hand contact of sequence switch' spring 361 to grounded-,battery over the circuit previously described. Relay 510 becomes energized.

In response to the depression of the No. 4 units key, a circuit is completed from ground through this key, conductor 512, lett-hand winding of relay 513, conductor 514, upper right-hand contact of sequence switch spring 362 to grounded battery overthe circuit previously described. Relay -513becomes energized.' f

As ysoon as'the relays 510 and513 become energized and attract'their armatures` a locking circuit for these relays is completed from grounded battery, conductor 516, right-handwinding and right-hand ar- Y mature and front contact of relay 510, con- Y ground throughV this key, conductor 509, leftductors 517, 518 and 519, right-hand win-.l-

ing and right-hand armature and front con- -tact of relay 513,`conductor 520, winding of relay 324, lower contact of sequence Switch springfae to ground. Riay ssabegrounded battery, left-hand winding of relay 508, conductor 521,' right-hand winding and right-hand armature and front contact of relay 501, conductor 522, right-hand winding of relay 504 (this relay being energized so that the shunt circuit around this winding isropen), conductor 523, righthand winding and right-hand armature and front contact of relay 506, conductor 524, winding of relay 326, armature and front contact of relay 324 to ground. As soon as the relay 326 becomes energized, a circuit is completed from grounded battery, power magnet sequence switch 300, armature land front contact of relay `326, contacts of sequence switch spring 325 to ground, for moving the sequenceswitch out of position 3 and into position 4.

'lVhen sequence switch 300` reaches vposition 4 a circuit is closed from grounded battery, lower contact of sequence switch spring 327, conductors v345, 346, windings of inagnets 532, 533, 534, 535 in parallel to ground. rllhese magnets, upon energization, release the depressed keys, the relays that were originally energizedr through contacts of these keys being held up through the above traced locking circuits with theexception of relay 402, which becomes deenergized.

The deenergization of relay 402, completes a circuit Afrom grounded battery, winding of power magnetsequence switch 300, upper cont-act of sequence switch spring'329, lefthand armature and back contact of relay 402, upper right-hand contact of Vsequence switch spring 405 to ground, for moving the sequence switch 300 out of position 4 and into position 5. A circuit is now completed from grounded battery, power mag-- net of sequence switch 400,1contact of sequence switch spring 328, lower left-hand contact of sequence switch spring 405 to ground, for moving the sequence switch out of position 1 and into position 2.k In this position of the allotter the sequence switch associated with another cord finder is moved into position 1 in a manner to be liereinafter described. In position' 2 of sequence switch 400, relay 402 is energized'over a circuit extending from ground, lower righthand contact of sequence switch spring 405, resistance 411, winding of relay 402, lower right-hand contact of sequence switch spring- 403 to grounded battery. Through the attraction of its right-hand armature relay 402 maintains full potential on coiiductoi` 346 through the contact of sequence switch spring 412 until another cord finder has een allotted. As will hereinafter appear, when a Vcordiinder completes its task and mores into Vposition 18 it rests there until the one preceding it in order has been taken foriise. 'In' the present case the cord iinder shown in Fig. 3 precedes anotherv whose conductor 361. which corresponds to conductor 360 of the present case, is connected to the sequence switch spring 405 in vposition 4. When therefore the present cord finder goes into use and in the manner described thesequence switch 400 is moved into position2, a circuit will be closed from ground, contact of sequence switch spring 362 which Vbelongs tothe next cord finder, contact of 'sequence switch spring 410. motor magnet 400 to grounded battery. Sequence switch 400 moves into position 4, where the next cord finder is then allotted.

In'positions 2 and 5 of sequence switches 100 and 300 respectively,a fundamental circuit is closed from grounded battery, wind-- ing of relay 113, lower and upper right-hand contacts of sequence switch spring 114, conductor 115, terminal 330, brush 331, conductor l332, contact of sequence switch spring 333,`resistance 334, winding of relay conductor 336, armature and back Contact of counting relay 0 to ground. Relay 113 becomes lenergized and completes a locking circuit for itself through its left-hand armature and front contact and the lower left-hand contact of sequence switch spring 'y 114. Relay 335 closes a circuit from grounded battery, winding of counting relay 3, ar- -inature and back Contact of counting relay 3, conductor 526, left-hand armature and front contact of relay 501, conductor 340, upper contact of sequence switch spring 330,

upper right-hand cont-act of sequence switch spring 338, armature and front contact of relay 335, to ground. Counting relay 3 closes a locking circuit for itself from grounded battery, through its winding,

winding of counting relay 3, armature and front contact of counting relay 3, conductoi 342, contact of sequence switch spring 343 to ground. Relay 3 does not become energized at this time due to the shunt around its winding through the front contacts of relays 501 and 335.

The energization of relay 113 closes a circuit'froin grounded battery, power magnet of sequence switch 100, upper contacts of sequence switch spring 116, right-arm armature a'nd front contact of relay 113 to ground, for driving the Vsequence switch 100 out of position 2 and int-o position 3.

In positions 3 to 13' ofsequence switch 100 a circuit is closed from grounded battery, lamp 11T, lower right-hand and upper left-hand contacts of sequence switch spring 118, interrupter 119 to ground. The flash@ ing of they lamp 11T indicates to the B operacuit previously described.

left-hand contacts of sequence switchspring 121, rightfhand armature and front contact of relay 113 toground. Under the control oftheup-drive magnet 120, the wipersand brushes carried by therod 121 are elevated.

.As soon .as the commutator brush 122 vengages a conductingportionofthe commutator segment'y 123, 'a shuntcircuit is closed around the winding of relay 335, from 'grounded battery, winding oi relay 113,*leli'thand armature and front contact of relay 113, lower left-hand contact of sequence switch spring 114, upper left-hand contact ot sequencey switch springi124, conductor- 17 5, conducting segment of commutator 123,

`brush 122, conductor 125, upper left-hand Vcontact of sequence switch spring 126 vto ground. This shunt circuit causes lthe deenergiZa-tion of-relay 335, -w iereupon the relay 3 energizes in series with relay over the cir- They energization r of relay 3 extends the conductor 526 through the armature and back contact of v,relay 2,

the fourth conducting segment, whereuponcloses a locking circuit for itself from grounded battery, win-ding of relay 2, Ywinding off relay2, armature and front contact ofvv relay 2, conductor 342, contact-of se-l quence switch spring 343 to ground. The

` relay 2 is permitted toenergize as soon as vthe relay 335 is deenergized, 'due tothe -fbrush 122 engaging the second conducting segment of commutator v123. v This operation continues until-the brush 122 engages the common Arelay O is energized and opens at its back contact the fundamental circuit, lcausing the deenergization of relays 313 and 335. The deenergization of relay 113 opens the circuit of the up-drive magnet 120, whereupon the brushes ofthe selector are arrested with each set of brushes in opl erative relation to the irst set otterminals in each sectionY of the terminal banlriespectively. The deenergization of relay 113 also closes a circuit from grounded battery, power magnet of sequence switch 100, lower left-hand contact of sequence switch spring 127, right-hand armature and back contact of relay 113 to ground, for moving the sequenceswitch out of position 3 and into position 4.

Relay 0 also closes a circuit from grounded battery, power magnet o1 sequence switch 300, lowerleft-hand contact of sequence switch spring 329, conductor 344, armature and front contact of relay 0 to ground, for moving the sequence switch 300 out ofposition 5and into position 7. While Vthis sequence switch is moving from posivcircuit is completed-from groundedbattery, windingof trip magnet 128, upper righthand contacto` sequence yswitch spring' 126 to ground. Trip magnet 128 becomes energized and moves a tripping finger 131 opposite a catch (not shown) provided on a cam, which holds the wipers apart and out of contact with the terminal bank.

` lVhe'n the sequence switches 100 and 300 reach positions 4 an'df?. respecti'yely the fundamenta-l circuit is lagain closed, causing the energization of-.relays335 'and 113.

The" energization of rela-yQ335fcloses a circuit from grounded battery, winding of counting relay 3, armaturefand backcoutact v of counting relay 3, conductor 526,

conductor "577, right-hand armature and 'front contacto'frelay 528, left-hand armature and' iront contact of relayv 504, conductor 529, lower left-hand contact of sequence switch spring 339, upper right-hand Contact of sequence switchspri'ng 338,.armature and front contact of relay n335, to ground. Relay 113 completes acircuit from grounded'battery, power magnet of sequence switch 100, upper contacts of sequence switch springg116, right-hand armature and front contact of relay v113, to ground, for movingl the sequence switch 10Q out of position 4 and into position 5. VRelay 113 is held energized while thev sequence switch .100 is vmoving from position 4to position 5, by

a locking circuit'through its leithand armature an'd vfront contact and the lower vleithand contact of sequence switch Vspring 114.

ln position 5. of the sequence Vswitch the circuit ofthey up-drive lmagnet 120 `is again closed, and ythis magnetcauses the further upward trayel of the brush rod 121. Upon the initial movement of this brush rod the trip nger131 causes the removal of the cam irombetween the v wipers of the fourth set of brushes of thel selector. 'At the Vsame time a brush 129 engages a conducting segment of a commutator 130 and closes a shunt circuit around the winding of relay 335 from grounded battery, winding ot relay 113,le;tthand armature and front contact ofrelay 113, lower right-hand contact of sequence switch spring 114, upper righthand Vcontact of sequenceswitch spring 124, conductor 181, conducting segment of commutator 130., brush 129,7conductor 125, upper left-hand'contact of sequence switch spring 126 to ground. The stepping relay 335 becomes deenergized and permits the energization of relay3. As soon'as the brush 129 engages an insulated segment ofthe commutator. the shunt circuit is opened and the relay 33:3is again energized. During the successive engagement of the brush 129 with the commutator 130, the stepping rela-y 335 is operated to cause the` actuation ot the counting relays in the above described manner until the 0 relay is energized.. The fundamental circuit is then opened and the relays 113 and 335 dcenergized.. The relay 113 is, however, held energized until the brushes are properly centered on the first set of terminals oi the selective group, which in the present case is the fourth group, by a circuit from grounded battery, winding ot relay 113, left-handY armature and front contact ot relay 113, lower lett-hand contact ot sequence switch spring 114, upper righthand Contact of sequence switch spring 124, conductor 181, conducting portion ot commutator 130, brush 129, conductor 125, upper lett-hand contact of sequence switch spring 126, to ground. As soon as the brushes are properly centered, this circuit is opened and relay 113 deenergized, whereupon the circuitotthe up-drive magnet 120 is opened. A circuit is also completed 'from grounded battery, power magnet osequence switch 100, lower lett-hand contact o1 sequence switch spring 127, right-hand armature and back contact of relay 113 to ground, moving the sequence switch into position 6.

TheI energization of counting relay 0 also completed a circuit 'from grounded battery, winding o1 pow-er magnet 300, lower lett-hand Contact of sequence switch 329, conductor 344, armature and front Contact o1 counting relay 0 to ground, for moving sequence switch out ofl position T and into position 9. kVhile sequence switch 300' is moving from position 'T to position .9 lthe locking circuit or" the counting relays is opened at the Contact of sequencel switch spring 343. Y

1n position 6 of the sequence switch 100 a circuit is closed from grounded battery, the right-hand winding o1 relay 108, lower contact of sequence switch spring 132, to ground. Relay 108 closes a circuit from groundedbattery, power magnet 100, upper and lower le'lt-hand contacts of sequence switch spring 116, left-hand armature and trent contact o1 relay 108, upper lett-hand contact of sequence switch spring 109 `to ground. lor moving sequence switch 100 out oit position 6 and into position 7. 1t the brushes 133, 134 and ot the selector are in engagement with the terminal ot a busy line, ground will be found upon the test terminal 136 thereof so that the relay 108 will still be energized inposition 7 due to a circuit from grounded battery, lett-hand windingo1 relay 108. lower right-hand contact of sequence switch spring 137. right-hand armature andiiiront contact of relay 108, conductor 138, resistance 139, brush 134, tertion o.

minal 136, to ground. The energization of relay 108 in position 7 ycloses a circuit from grounded battery, winding of up-drive ma gnet 120, left-hand contacts of sequence switch spring 121, upper right-hand and lower lett-hand contacts ot sequence switch spring 116, left-hand armature and front contact of relay 108, upper lett-hand Contact ot sequence switch spring 109 to ground. Under the control of the up-drive magnet 120, the brushes 133, 134 and 135 are again moved upward until they engage the terminals ot' an idle trunl; which does not hare ground connected to its test terminal. The relay 108 will then deenergize and complete a circuit from grounded battery, power magnet et sequence switch 100, lower vcontact ot Vseuence switch sninfr 140. back contact and vleft-hand armature of relay 108, upper lett-hand contact of sequence switch spring 109, to ground, for moving the sequence switch 100 out o1' position T and into posi- O Relay 108 will remain energized, however, until the brushes are accurately centered on the terminals of the idle trunk due to a circuit being closed from grounded battery, right-hand winding of relay 108, upper contact of sequence switch spring'132, conductor 182, conducting portion of vcoininutator 183, brush 184, conductor 125. lower contacts of sequence switch spring116, lefthand armature and front contact ot relay 108, upper lett-hand contact or' sequence switch spring 109 to ground. As soonas the brushes are actually centered this circuitis opened by the brush 184 engaging an insulated portion o't the commutater 183.

1n position 8 ground is connected to the test terminal 136 ot' the selected trunk through the upper right-hand contact of sequence switch spring 109, conductor 138, resistance 139 and test brush 134.

Then the sequence switch 100 reaches position 8 and the sequence switch 300 reaches position. 9, the fundamental circuit is again closed, causing the energization of relaysY 113 and 335. The relay 113 again completes a locking circuit tor itself through its lefthand armature and 'front contact and the lower lett-hand contact of sequence switch springl 114. The energization oit relay 113 also closes a circuit 'trom grounded battery, power magnet oi sequence switch 100, upper contacts ot sequence switch spring 116.` right-hand armature and front contact of relay 113 to ground, 'for moving sequence switch 100 into position 9.

As soon as the sequence switch 100 reaches position 9 a circuit is completed from grounded battery, contact ot sequence switch spring 201, right-hand winding of relay 202, lower left-hand contact otsequence switch spring 203, conductor 204, terminal 141, brush 133, lower right-hand and upper letthand contacts et sequence switch spring 121,

front Contact and right-hand armature of relay 113 to ground. Relay 202 is energized andy closes a ,Circuit from grounded` battery, winding lof relay 205, lower left-hond and upper righthand contacts ot sequence switch spring` 206, lett-hand armature and lront Contact of relay 202, to ground. Relay 205 closesA e locking circuit for itself troni grounded battery, winding et relay 205, right-hand armature and front Contact of: relay 205,' resistance 20T, conductor 208, brush 13d, resistance 139, conductor 138, ,upper right-hand contactotl sequence switch lr-ing 109, to ground. Relay 205 also closes a circuit `trom grounded buttery, power inegnet of sequence switch 200, upper right-hand Contact of sequence switch spring 209, lettf hand armature and front Contact of relay 205 to ground, for moving the sequence switch 200 out or position 1 and into position over the circuit previously described.

ln position 2 of sequence switch 20G a circuit is Closed from grounded buttery, winding ofup-drive magnet 211, conductor 212, lett-hund contacts oi sequence switch 210, right-hand armature und iront contact or' relay 202, lower right-hund Contact ot' se quenee switch spring 203 to ground over the circuit previously described. Under the con- Y trol of the u i-drive magnet 211 the brush rod 213 is elevated.

The energization ot relay due to the fundamental circuit being closed, completed a Circuit from groundedbattery, winding of the counting relay 1, armature and hurl; contact ofiz counting relay 1', conductor 530, letthend armature and 'Front content of relay 50G, conductor 531, lower right-hand contact voli-sequence switch spring 339, upper right-hand Contact( uquenee switch spring 333, armature and il'ront Contact of relay 835 to ground. lounting relay 1 completes a. locking circuitfor itself through the winding ot' counting relay l, arnmture and trout contact oit counting relay l, to ground, over conductor 34:2. rllhe counting relay l. is not energized at this time, due to the shunt around its winding through the' front contaets o1 relays 506 and 335.

As soon as the commututor brush 214; engegesthe conducting segment ot" the commutator 215, a circuit is closed trom grounded battery, winding of relay 11B, left-hand arma-ture and tront contact o1 relay 118, lower and upper lett-hand contacts ot ,sequence vswitch spring 114, coiiduetor 143, hrush '135, terminal 1411!, conductor iii-5, lcfiftground.

grounded l attery, power magnet or 'for hund Contact of sequence switch spring 21'?, conductor 218,7npper right-hond contact et sequence switch spring 219, conducting segment o1 commutator 215, brush 2.14 to Due to the closure oi this shunt path, the relay 5335 becomes ,fleenergized end permits the energization ot the counting relay 1. is soon as the-commutator brush 214C 'engages thelirst insulatingV Vsegment oli the connnutator 215, the'nhove traced shunt path is opened and the relay 33- 5 is again energized, whereilpon the counting re` ,y O becomes energized. The connector continues to more upward until the brush 214- engages the second conducting segment ot the commutstor 215, at which time the deenergination o relay permits the energization ot' the counting relay GQ The fundamental circuit Aisthen opened und relays 335 and 113 heeoine deenergized rllhe energization of counting relay 0 also closes a circuit from e/.pience switch 300,.lower lett-hand contr-.et ot sequence switch spring 32S, conductor 31%,

armature and 'front Contact ot 'counting` rr lay 0 to ground, moving the sequence switei` 800 out oi.V position 9 Aand'into position 1 whereupon the locking oireuit et the coun ingY relay is opened. "l

The d'eenergizetion of relay 118 opens eircuitsior relay 202 and mi",` f' deenergization ot relay I3 i.. cuit from grounded battery, of sequence switch 100, lof-.ver le-@ttaet of sequence switch spring hand armature and haelt Contact of relay 118 to ground, for moving the sequence switch out of position 9 and into position 10.V

i rightvThe deenergization otrelay 202 closes a.V eireuit from grounded buttery, power msg net, sequence switch 200, lowerright-hand and upper lettlhand contacts ot sequ nce switch spring` 206, left-hand armature end bock Contact of relay 202 grounti, for moving the sequence switch out position 2 und into position 3. Y

lilith sequence switches 100km/l w sitions 1i) and 11 respectively,the 'rendan mental circuit is again closed und reluys 113 and 335 hecomeenergized.' 'lfhe ener Kaution olfirclu'y 1,13 closes the ahore traeed circuit morning the sequence switrh 10 and into position 11 und tor energi'fzing relay Q02, Y Y Y rlhe energization olE relay 202 closes a cirenit from grounded buttery,

right-hand contacts orp sequence switch 206,

1011) out otpower magnet Y 'ot sequence switch 200, lower and upper lettdmnd armature und front Contact o1 ref lay 202 to ground, for moi/'ing the sequence switch into `position d, whereupon the circuit tor updrive magnet 211will again he establisln-u'l through the Vlor-fer and upper letthand contacts ot' sequence switch spring 210. lllheu the sequence switch "300 reached posi- 'tion 3, a circuit was closed from grounded battery, winding of trip magnet 220, contact of sequence switch spring 221 to ground. rl`his magnet moves a trip inger 222 into a position such that upon the next upward movement ofthe brush rod 213, a set ot brushes may be tripped.

The energization o1 relay 335 due to the closure oit the fundamental circuit completes a circuit from grounded battery, winding of counting relay 5, armature and back contact of counting relay 5, conductor 536, left-hand armature and front contact of relay 510, conductor 537, lower left-hand and upper right-hand contacts of sequence switch spring 338, armature and front contact of relay 335 to ground. Counting relay 5 becomes energized and prepares a circuit 'for counting relay 5. As soon asthe brush 224V engages a conducting segment of commutator 225, ground 1s connected to the conducvtor 218, and stepping relay 335 is shunted out and permits the energization 'of counting'relay 5 in the same manner as above described. Then the brush 224 engages the `first insulating segment of the'commutator 225, the stepping relay 335 is again energized, whereupontherelay t is energized. The operation ot' the counting relays under the control of the stepping relay 335 continues until in response to the sixth engagement of the brush 224 with a conductive segment of the commutator 225, the countingrelay 0 becomes energized and opens the fundamental circuit, thereby causing the deenergization of relays 113 and` 335. The energization of counting relay 0 also closes a circuit previously described, for moving the sequence switchf300 out ot position 11 andinto .position 13. The deenergization of relay113opens-the circuits ot relay 202 and magnet 211 and also completes a. circuit from grounded battery, power magnet of sequence switch 100, lower lett-hand Contact of sequence switch spring `127, right-hand armature and back contact ot relay 113 to ground, 'lor moving the sequence switch into position 12. The deenergization o'lrelay 202 completes the circuit previously described for moving the sequence switch 200 out ot position fl and into position 5.V The magnet 220 ybecomes deenergizedas soon as the sequence switch 200 leaves position 41.

lVhen the sequence switches 100 and 300 reach positions 12 and 13 respectively, the fundamental circuit is againclosed, whereupon the relays 113 and 335 become-energized. Relay 113 again Y closesla circuit through the' upper contacts of' sequence switch spring 116 ttor moving the sequence switch 100 out of position 12 and into position 13. This relay also closes a Vcircuit for causing the energization of relay 202, which by attracting its left-hand armature completesl circuit-trom sequence switch 200, :tor

moving the sequence switch out of position- 5 and into position G.

AIn position 6 o1" the sequence switch V200, a circuit is closedr lrom grounded battery, winding oit 11p-drive magnet 226, conductor 227, lower right-hand and upper lett-band contact ot sequence switch 210 and then to ground at the right-hand armature and front contact o't' relay 113. Under the control of magnet .226, the brush rod 213 is elevated at a slower rate of speed than under the control ot the up-drive magnet 211.

lUpon the energization of relay 335, when the fundamental circuit was closed, a circuit was completed from grounded battery, winding ot counting relay 4, armature and back contact ot counting relay L1', conductor 538, lett-hand armature and front contact ot relay 513, conductor 539, upper contacts of sequence switch spring 338, armature and front contact ot' relay to ground. Counting relay 4; becomes energized and prepares a circuit forcounting relay 'l.

As the brush rod 213 iselevated under the control ot magnet-226, the brush 214 again connects ground through the commutator 215, upper right-hand contact of sequence switch spring' 219, conductor 218, lower letth'and contact ot sequence switch spring 217 conductor 145 to the winding of relay 113, causing thus the denergization ot relay 335; As soon las this shunt circuit has been closed tive times, the counting relayO is again energized, whereupon the fundamental circuit is Aopened and the relays 113`and become dcenergize'd. The counting relay 0 closes the previously described circuit `tor sequence switch 300 for moving it out of position 13 and into position'lG. The deenergization ot' relay 113 opens the circuits ot relay 202 and magnet 226, and also completes a circuit through the lower left-hand` contact of sequence switch spring 127 for moving the sequence switch 100 out ot position 13 and into position 14. The deenergir/.ation ol" relay 202 conipletesa circuit itroin grounded battery. power magnet ol sequence switch 200, lower right-hand and upper lett-bami contacts ol sequence switch spring 206, letthand armature and back contact of relay 202 to ground, vfor moving the sequence switch 200 out or" position G and into position 7.

f As soon as the sequence switches 100 and 200 reach positions 1l and 7 respectively, a, circuit is completed Afrom grounded battery, upper contact ot sequence switch spring 201, rightshand winding oi' relay 202, lower letthand contact of sequence switch spring 203, conductor 2011, terminal 14:1, brush 133,

-lower vand upper right-hand contacts ot' sequence switch spring 121, conductor 147, upper armature and back contact otrelay 148, upper right-hand winding ot repeating coil 1&9 to ground. Relay 202 completes a circuit from grounded battery, power niagcontact of relay 202 to ground, for moving the sequence switch out of position 7 into position 8.

It will first be assumed that the called line is idle and full battery potential is connected to the test terminal 230. A circuit is then completed from grounded battery through the cut-off relay 231 'of the called line, terminal 230, brushes 232, conductor 233, lower right-hand contact vof sequence vswitch spring 234, left-hand winding of relay 235, lower contacts ofY sequence switch spring 236, right-hand Winding of relay 235 to ground. Relay 235 Vbecomes energized and closes a locking circuit for itself through its left-hand low resistance windingand its left-hand armature and front contact to ground at the left-hand armature and back contact .of relayV 237. Due to the closurerof this circuit, the potential at the test terminal 230 and multiples thereof is reduced so as to prevent the seizure of this line by another selector switch. The energization of relay 235 also completes a circuit from grounded and battery,'power magnet of sequence switchY 200, lower left-hand contact of sequence switch spring 209, conductor 238, right-hand armature and front contact of relay 235,

right-hand armature and back Contact of relay 237 to ground, for moving the sequence switch out of position 8 and into position 10. This sequence switch is immediately moved out of position 10 into position 14 by a circuit from grounded battery, power magnet of sequence switch 200, lower righthand(v and upper leftehand contact of sequence switch spring 206, `left-hand armature and back contact of relay 202 to ground. Relay 202 was deenergized due to its circuit being opened at the lower left-hand contact of sequence switch spring 203, when the sequence switch 200 leaves position 75;. Sequence switch 200 is immediately moved out of position 14 into position 16, due to the circuit previously described for moving it out of' position 8.'

When the sequence switch 100 reaches position 14, a circuit is jcompleted from grounded battery, lamp 150, upper righthand and lower left-hand contacts of seque-nce switch 118 to ground. The steady lighting of the lamp 150 indicates to the B operator that connection has been established to the called party and that the apparatus is now in condition for ringing the called party. The B operator then depresses the ringing key 151, which completes a circuit from grounded battery, winding of relay 152, closed contact of ringing key 151 to ground. Relay 152 closes a circuit from grounded battery,

104, armature and front contact of relay 152, contact of sequence switch spring 111' to ground, for moving the sequence switch out of'poston 14 and into position 15. The sequence switch 100is immediately moved out of position 15 due to a circuit being closed from grounded battery, power magnet `ol sequence switch 100, upperleft-hand contact of sequence switch spring 127, conductor 175, upper left-hand and lower contactsV ot sequence switch spring 124 to ground.' The sequence switch is stopped in either position 16 or position 17, depending upon the condition of relay 108. i

Under the conditions assumed, when the sequence switch 100 reachesposition 12, circuit is completed from grounded battery, left-handwinding of relay 108, upper righthand contactrof sequence switch spring 137, conductor 154, terminal348, brush 349conductor 35,0', outer left-hand armature and front contact of relay 508 to ground. 'This circuit is maintained closed until the se? switch spring 140, right-hand` armature and front contact of relav 108, `upper right-hand contact ofsequence switch springi109 to ground, for movingthe sequence switchpinto position 17. As soon as the sequence switch 100 leaves position 169;, the 4:energizingcircuit of relay 108 is opened, thereby causing the deenergization of relay 108, which in turn opens the holding circuit of relay 305. The deenergization of relay 305 completes a circuit from grounded battery, power vmagnet of sequence switch 300, upper contact of sequence switch spring 304,1left-handv armature and back contact of. relay 305 to ground, for moving the sequence switchout of position 16 and into position 17. A circuit is now closed from grounded battery, winding of. down-drive` magnet 352, conductorY 353, lower andupper right-hand contacts of sequence switch spring 302, left-hand armature and back contact of relay 305 to ground.Y

Under the control of the down-drive magnet 352, the brush shaft 308'is returned to its normal position. As soon asthe normal position is reached, the brush 315 engages the normal conducting segment 354 and a circuit is completed from grounded battery, power magnet of sequence switch 300, upper right-hand contact of sequence switch spring 355, conducting segment 354,*brush 315 to ground, for moving lthe sequence switch out n 17 and into position 18, wherecncuit ot down-drive magnet 352 's soonas the power magnet ot sequence ch 00 is moved into position 17 a circloscd from grounded battery, power magnet oit sequence switch 400, contacts ot nce switch spring 110, contact oit sequence switch spring to ground, tor

the sequence switch 100 into position 1. 2i. circuit is thereupon closed from grounded battery, power magnet ot sequence switch 800, iower right-hand contact of sequence switch spring lower lett-hand et sequence switch spring 105 to This circuit causes the sequence move out of position 18 and into tion 1, thereby allotting this cord finder p08; tor service.

iihcn the relay 108 became deenergized iu position 161A et sequence switch 100, a circuit was completed trom grounded battery, lower lett-hand and upper right-hand contacts or' sequence switch spring 110, bach contact and lctt-hand armature or relay 108, conductor 158, armature and back contact ot' marginal relay 159, armature and back contact ot relay 160, winding of ringing relay 141:8, conductors 161 and 162, upper contacts of sequence switch sprinO 163, contacts ot' ringing lrey 151 to ground. The relay 148 becomes energized, but the relay 160 is prevented from becoming energized in series with relay 148, due to a shunt around its winding through its bach contact and the back contact or relay 159. Upon energization, relay 1418 closes the ringing circuit which extends from a grounded source ot ringing current through the right-hand winding ot relay 159, right-hand contact of sequence switch spring 164:, lower armature and front contact o1 relay 1-18, contact ot sequence switch spring 165, conductor 143, brush 185, terminal 1414;, conductor 1/15, contacts of sequence switch spring 217, brush 2%0, terminal 2&1, bell at substation No. 7654, terminal 242, brus 243, conductor 2411, upper contact or" sequence switch spring 203, conductor 204, terminal 1411, brush 133, lower Vand upper right-hand contacts of sequence switch spring 121, conductor 1&7, upper armature and iront contact of relay 148 to ground. lis soon as the called subscriber removes the receiver from the switchhoolr, suicient current is allowed to How through the ringing circuit to cause the relay 159 to attract its armature. rllhis movement ot the armature et relay 159 removes the shunt from around the winding ot relay 160, which then becomes energized.v Relay 160 by attracting its armature closes a locking circuit 'for itself over conductor 162 to ground through the ringing key. This locking circuit closes a shunt circuit around the winding ot relay 1118, which becomes deenergizerl and completes the talking circuit between the calling and called party. As soon as the relay 1418 deenergizes, a supervisory relay 166 becomes energized and completes a circuit tor the supervisory relay 167. The supervisory relay 167 becomes energized and connects ground to conductor 162 for maintaining the relay 160 energized after the operator releases the ringing key 151.

lWhen disconnection is desired and the called subscriber restores his receiver to the switchhoolr, the relay 166 becomes deenergized and opens the circuitof relay 167. Relay 167 opens the circuit ot relay 160 and also actuates a well-known supervisory signal at the A operators position. The operator after receiving the signal fromr the called subscriber removes the plug 101 from the jack 102. The deenergization of relay 167 opens the circuit of relay 152, which deenergizes and closes a circuit from grounded battery, lower and upper left-hand contacts ot sequence switch spring 110, winding of relay 106, armature and back contact ofv relay 152, brush 167, interruptor 168 to ground. When the interrupter 168 closes its circuit, relay 106 becomes energized and closes a locking circuit tor itselic through its left-hand armature and front contact. Relay 106 also closesacircuit from grounded battery, winding of relay 113, conductor 17 0, upper contact-s of sequence switch spring 105, right-hand armature and trout contact of relay 106, brush 169, interrupter 168, to ground. As soon as the interruptor 168 closes this circuit, relay 118 energizes and closes a circuit from grounded battery, power magnet ot sequence switch 100, upper contacts of sequence switch spring 116, right-hand armature and Yt'ront contact of relay 113 to ground, for moving the sequence switch into position 18. In position 18 a circuit is closed from grounded battery, windingo'f down-drive magnet 172. lower contact oit sequence switch spring 126 to ground, for returning the brush rod to normal. ris soon as the brush rod reaches its normal position, a circuit is closed trom grounded battery, power magnet of sequence switch 100, lower right-hand contact of scquence switch spring 127, normal conducting segment 175, brush 129, conductor 125, upper left-hand contact of sequence switch 126 to ground, for moving the sequence switch into position 1, whereupon the circuit ot the down-drive magnet 172 is opened.

.fis soon as the sequence switch 100 leaves position 17, the circuit of relay 205 is opened at the upper right-hand contact of sequence switch spring 109. This relay becomes deenergized and closes a circuitfrom grounded battery, power magnet oit sequence switch 200` upper left-hand contact of sequence switch spring 209, left-hand armature and back contact of relay 205 to ground, for

moving the sequence switch 200 out of position 16 and into position 18. In position 18, a circuit is closed from grounded battery. winding of down-drive magnet 250, lower contact of sequence switch spring 251 to ground. Under the control of the downdrive magnet 250, the brush rod of the connector switch is returned to its normal position. As soon as the brush rod reaches its normal position a circuit is closed from grounded battery, power magnet of sequence switch 200, lower right-hand contact of sequence switch spring 209, conductor 252, conducting segment 253, brush 224 to ground, for moving switch 200 out of position 18 and into position 1, whereupon the circuit of the down-drive magnet 250 is opened. Y y

, If the called line had been busy, the potential on the test terminal 230 and multiples thereof would have been reduced, due to the low resistance path closed through the lefthand low resistance winding of a relay similar to relay 235. In this case, upon the movement of the sequence switches 100 and 200 into positions 14 and 8 respectively, the marginal relay 235 does not become energized. A circuit is closed at the connector switch from grounded battery, left-hand and right-hand winding of relay 202, uppervandv lower left-hand contacts df sequence switch spring 254, armature and back contact of relay 255, right-hand armature and back contact of relay 235, right-hand armature and back contact of relay 237 to ground, for maintaining relay 202 energized. Relay 202 closes a circuit from grounded battery, power magnet of sequence switch 200, lower and upper right-hand contacts of sequence switch' spring 206, left-hand armature and.y front contact olf relay 202 to ground, for

moving the sequence switch 200 out of position 8 and into position 10. Relay 202 is still maintained energized in position 10 due to the circuit previously described. cuit is now closed from grounded battery, winding of up-drive magnet 226, conductor 227, lower right-hand and upper lett-hand contacts of sequence switch spring 210, righthand armature and `fro-nt contact ot relay 202, contact 257, lower andupper left-hand contacts of sequence switch spring 258 to ground. Under the control ott the upv-drive magnet 226, the brush shaft 213 moves upward until the brush 224 engages the overflow contact 259. A circuit is then closed from grounded battery, power magnet of sequence switch 200, lower contact of sequence switch spring 260, conductor 261, overflow` contact 259, brush 224 to ground, for moving the sequence switch 200 outl of position 10 and into position 14. In position 14, a circuit is closed' from grounded battery, winding of down-drive magnet 250, upper contact olf sequence switch spring 251, right- A ciri hand armature and back contact of relay 235, right-hand armature and back contact of relay 237, to ground, `for returning the brush rod 213 to its normal position. As soon as the normal position is reached, a circuit is completed from grounded battery, power magnet of sequence switch 200, lower right-hand contact of sequence switch 209, conductor 252, normal contact 253, brush 224 to ground, for moving the sequence switch 200 out of position 14 through position 16 to position 17. kAs soon as the B operator depresses her ringing key and sequence switch 100 moves in position 17, a circuit is closed from ground, resistance 262, interrupter 263, upper contacts of sequence switch spring 236, conductor 145, terminal 144, brush 135, conductor 143, contact ot sequence switch spring 165, lower armature and front contact of relay 148, right-hand winding of relay 159 to grounded source of ringing current. Relay 159 becomes energized and causes they energization of relay 160 and the deenergization of relay 148 in the manner above described. The circuit oi the 'interrupter 263 is then extended through the lower armature and back vContact of relay 148, winding olf supervisory relay 166, lower right-hand winding of repeating coil 149 to grounded battery. Relay 166 is intermittently energized and deenergized under the control of the interrupter 263 and causes the vibration of the armature of relay 166. The vibration of this armature of relay 166 results in thelash of a signal in the A operators position, whereupon this operator removes plug 101 from jack 102. Relay 167,v then remains deenergized and causes the release olf the selector switch in the same manner as above described'. As soon as test brush 134 of the selector switch leaves the test terminal 136, relay 205 becomes deenergized and completes a. circuit for moving the sequence switch' out of lposition 17, whereupon this sequence switch is returned to its normal position in the same manner as above described.

lt will now be assumed that the number ot the desired called substation is No. 7:154- and is on the same party line with substation No. 7654. The B operator will now depress the No. 7 thousands key, the No. 1 hundreds key, the o. 5 tens key and the No. 4 units key. The depression of these keys will result in the energization of relays 501, 504, 506, 510 and 513 in the same manner as above described. But the depression ot the No. 1 hundreds key does not cause the energization of relays 508 and 528 as did the depression of the No. 6 hundreds key. The operation ott the selector and connector switches under the control ot the register relays will be the same as above described eX- t'acts served by the .fourth set of brushes will cept that a trunk in the lirst group of conbe selected. This selection is determined in position 7 of sequence switch 300 by the tollowing circuit; grounded battery, winding of counting relay 2, conductors 600 and V601, right-hand armature and back contact of relay 528, left-hand armature and front contact of relay 504, conductor 529, lower lefthand contact of sequence switch springBBr' to ground at'the armature and front contact of relay 335. Y

It is not believed that a complete description of the operation of establishing a connection to the called line No. 7154 is necessary, as it will be obvious Ifrom the-above description how the sender will control the switches to establish a connection to the terminals 263, 264 and 265 of this line.

When the sequence switch 100 moves from position 13 into 14. after the last series of impulses, the holding circuit of relay 305 is opened at the lower left contact of sequence switch spring 109. This relay deenergizes at this time and causes the restoration of the cord finder, since the circuit for relay 108 is not completed at the outer armature and front contact of relay 508 in positions 12 to 16 of sequenceswitch 100. The

sequence switch 100 is moved out of posi-l tions 14 and 15 in the same manner as above described, but comes to rest in position 16. Ringing currentis now applied in position 16 through the left-hand winding of relay 159 instead of through the right-hand winding in position 17. This ringing current is of a diffe-rent characteristic and is arranged to operate the bell at substation 7154 only, where-as the ringing current through the right-hand winding is arranged to operate the bell at substation 7654 only. As soon as the called party answers, relay 160 is energized, causing the deenergization of relay 148, thus connecting the lines for communication. At the close of conversation relay 113 is energized over the circuit described and the selector and connector switches are returned to normal.

lVhat is claimed is:

1. In a telephone exchange system, the combination with panty lines, means including a selector and a connector switch for establishing a connection to one of said lines, a movable brush set for said selector, and means to position said brush set, of apparatus at said selector switch for applying selective signaling current to said party lines, a variably adjustable device for controlling the operation of Said switches, and means associated with said device and independent of said brush positioning means for controlling the operation of said signaling apparatus.

2. In a telephone exchange system, the combination with panty lines, means including a selector and a connector switch for establishing a connection to one of said lines,

a movable brush set -or said selector, and means to position said 'brush set, of apparatus at said select-or switch for applying selective signaling current to said party lines, an impulse transmitting mechanism arranged to. control the operation of said switches, a variably adjustable device for controlling said impulse transmitting mechanism, and means associated with said device and independent of said brush positioning means for controlling the operation of said signaling apparat-us.

3. In a telephone exchange system, the combination with party lines, means including a selector and a connector switch for establishing a connection to one of said lines. a movable brush set for said selector, and means to position said brush set, ot' sources of ringing current of diierent characteristics at said selector switch, a variably adjustable device for controlling the operation of said switches to establish a connection to a desired line, andmeans controlled by said device and independent of said brush positioning means for selecting the proper one of said sources of ringing current for signaling the desired party on said line.

4. In a telephone exchange system, the combination with party lines, means including a selector and a connector switch Jfor establishing a connection to one ot said lines, a movable brush set for said selector, and means to position said brush set, of sources of ringing current of different characteristics at said selector switch, a variably adjustable device for controlling the operation of said switches to establish a connection to a desired line, and a relay at said selector switch operative in accordance with the adjustment of said device and independent ot said brush positioning means tor controlling the selection of the proper source of ringing current for signaling the desired party on said line.

A5. In a telephone exchange system, the combination with party lines and means including a selector and a connector switch for establishing a connection to one of said lines, of mechanism at said selector switch for applying selective signaling current to said party lines, a controlling device comprising sets of keys and sets of register relays arranged to be selectively operated in response to the operation of such keys to control the operation ot said switches, and means also operated in response to the operation of said keys for controlling the operation ot said signaling mechanism.

6. In a telephone exchange system, the combination with party lines, means including a selector and a connector switch for establishing a connection to one of said lines, a movable brush set for said selector, and means to position said brush set, of apparatus at said selector switch for. applying selective signaling current to said party lines, a controlling devicel comprising sets ot keys and registering mechanisms arranged to be selectively operated in response te the operation ofvsaid keys to control the operation of said switches, and means controlled by said registering mechanisms and independent of said brush positioning means for controlling the operation or" said signaling apparatus. 4

7. ln a telephone exchange system, the combination with party lines, means including a selector and a connector switch for establishing a connection to one or said lines, a movable brush set Jfor said selector, and means to position said brush set, of appara` tus at said selector switch Jfor applying selective signaling current to said party lines, a controlling device comprising sets of keys and registering mechanisms arranged to be selectively operated in response to the o eration or such keys to control the operaf tion or' said switch, and a relay controlled by the operation of such keys and independent of said brush positioning means for controlling the operation of said signaling apparatus. v

8. ln 'a' telephone exchange system, the combination with party lines, means including automatic switches for establishing a connection to one ot said lines, movable -sets ot' keys and registering mechanisms arranged to be selectively operated in response to the operation of said keys to control the operation of said switches, and means controlled by the condition of said mechanisms as determined by the operation of said keys and independent of said brush positioning means for controllingl the operation of said 'apparatus tor applying selective signaling current to said party lines. y

9Qln Va telephone exchange system, the combination with party lines and means including` automatic switches for establishing a connection to onev o'l' said lines, ot' mechanism for vapplying selective signaling current to said party lines, a controlling device comprising sets of keys and sets of register relays Varranged to be selectively operated in response to the operation of said keys to control the operation of said switches, and means also operated in response to the operation of said keys for controlling the operation of said signaling mechanism.

in witness whereof, hereunto subscribe my name this 27th day o1 September', A. D.

Y ALBEN E. LUNDELL. 

